Bilateral auditory prosthesis systems (i.e., auditory prosthesis systems that provide electrical stimulation to both ears of a patient) offer many advantages in terms of performance over conventional auditory prosthesis systems that are capable of only providing electrical stimulation to one of the patient's ears. For example, by applying electrical stimulation to both ears of a patient instead of one, bilateral auditory prosthesis systems (e.g., bilateral cochlear implant systems) are capable of providing a more realistic representation of audio content to the patient.
Unfortunately, however, bilateral auditory prosthesis systems typically require two externally worn sound processors—one for each ear. This makes bilateral auditory prosthesis systems costly to implement and maintain. Dual sound processors are also cumbersome, bulky, and aesthetically unpleasing for many patients.
One attempted solution to this problem has been to connect two electrode arrays (or “electrode leads”) to a single auditory prosthesis that is implanted on a particular side (e.g., the right side) of a patient's head. One of the electrode arrays may be implanted on the same side as the auditory prosthesis and the other may be implanted on a contralateral side (e.g., the left side) of the patient's head in order to facilitate bilateral electrical stimulation of sites located within both ears of the patient. A single sound processor may then be used to direct the auditory prosthesis to apply electrical stimulation to both ears.
A particular problem with this approach is that the electrode array configured to be implanted on the contralateral side has to be tunneled from the implant site of the auditory prosthesis all the way across the patient's head in order to reach its intended destination. Because the electrode array may include sixteen or more electrodes, a relatively large number (e.g., sixteen or more) of corresponding wires have to be tunneled across the head in this manner. Tunneling a large number of wires across the head can be difficult, dangerous, unreliable, and costly. Moreover, such a large number of wires may begin to bulge and/or otherwise bother the patient over the course of time. Finally, if the electrode array ever needs to be replaced in the future, a whole other set of wires will again have to be tunneled across the patient's head.